Grahamespensen9917

In vivo studies demonstrate that KD8@N-MCNs decrease Aβ deposits, ameliorate memory deficits, and alleviate neuroinflammation in the 3xTg-AD mouse model. Our work provides a biocompatible and non-invasive way to attenuate AD-associated pathology.Autophagy triggered by reactive oxygen species (ROS) in photodynamic therapy (PDT) generally exhibits an anti-apoptotic effect to promote cell survival. Herein, an innovative supramolecular nanoplatform was fabricated for enhanced PDT by converting the role of autophagy from pro-survival to pro-death. The respiration inhibitor 3-bromopyruvate (3BP), which can act as an autophagy promoter and hypoxia ameliorator, was integrated into photosensitizer chlorin e6 (Ce6)-encapsulated nanoparticles to combat hypoxic tumor. 3BP could inhibit respiration by down-regulating HK-II and GAPDH expression to significantly reduce intracellular oxygen consumption rate, which could relieve tumor hypoxia for enhanced photodynamic cancer therapy. More importantly, the autophagy level was significantly elevated by the combination of 3BP and PDT determined by Western blot, immunofluorescent imaging, and transmission electron microscopy. It was very surprising that excessively activated autophagy promoted cell apoptosis, leading to the changeover of autophagy from pro-survival to pro-death. Therefore, PDT combined with 3BP could achieve efficient cell proliferation inhibition and tumor regression. NU7441 Furthermore, hypoxia-inducible factor-1α (HIF-1α) could be down-regulated after tumor hypoxia was relieved by 3BP. Tumor metastasis could then be effectively inhibited by eliminating primary tumors and down-regulating HIF-1α expression. These results provide an inspiration for future innovative approaches of cancer therapy by triggering pro-death autophagy.Contact electrification (CE) at interfaces is sensitive to the functional groups on the solid surface, but its mechanism is poorly understood, especially for the liquid-solid cases. A core controversy is the identity of the charge carriers (electrons or/and ions) in the CE between liquids and solids. Here, the CE between SiO2 surfaces with different functional groups and different liquids, including DI water and organic solutions, is systematically studied, and the contribution of electron transfer is distinguished from that of ion transfer according to the charge decay behavior at surfaces at specific temperature, because electron release follows the thermionic emission theory. It is revealed that electron transfer plays an important role in the CE between liquids and functional group modified SiO2. Moreover, the electron transfer between the DI water and the SiO2 is found highly related to the electron affinity of the functional groups on the SiO2 surfaces, while the electron transfer between organic solutions and the SiO2 is independent of the functional groups, due to the limited ability of organic solutions to donate or gain electrons. An energy band model for the electron transfer between liquids and solids is further proposed, in which the effects of functional groups are considered. The discoveries in this work support the "two-step" model about the formation of an electric double-layer (Wang model), in which the electron transfer occurs first when the liquids contact the solids for the very first time.Multiple experiments provide evidence for photovoltaic, catalytic, optoelectronic, and plasmonic processes involving hot, i.e., high energy, electrons in nanoscale materials. However, the mechanisms of such processes remain elusive, because electrons rapidly lose energy by relaxation through dense manifolds of states. We demonstrate a long-lived hot electron state in a Pt nanocluster adsorbed on the MoS2 substrate. For this purpose, we develop a simulation technique, combining classical molecular dynamics based on machine learning potentials with ab initio nonadiabatic molecular dynamics and real-time time-dependent density functional theory. Choosing Pt20/MoS2 as a prototypical system, we find frequent shifting of a top atom in the Pt particle occurring on a 50 ps time scale. The distortion breaks particle symmetry and creates unsaturated chemical bonds. The lifetime of the localized state associated with the broken bonds is enhanced by a factor of 3. Hot electrons aggregate near the shifted atom and form a catalytic reaction center. Our findings prove that distortion of even a single atom can have important implications for nanoscale catalysis and plasmonics and provide insights for utilizing machine learning potentials to accelerate ab initio investigations of excited state dynamics in condensed matter systems.Single metal atom photocatalysts have received widespread attention due to the rational use of metal resources and maximum atom utilization efficiency. In particular, N-rich amorphous g-C3N4 is always used as a support to anchor single metal atoms. However, the enhancement of photocatalytic activity of g-C3N4 by introducing a single atom is limited due to the bulk morphology and the excess defects of amorphous g-C3N4. Here, we report crystalline g-C3N4 nanorod supported copper single atoms by molten salts and the reflux method. The prepared single Cu atoms/crystalline g-C3N4 photocatalyst (Cu-CCN) shows highly selective and efficient photocatalytic reduction of CO2 under the absence of any cocatalyst or sacrificial agent. The introduction of single Cu atoms can be used as the CO2 adsorption site, thus increasing the adsorption capacity of Cu-CCN samples to CO2. Theoretical calculation results show that reducing CO2 to CH4 on Cu-CCN samples is an entropy-increasing process, whereas reducing CO2 to CO is an entropy-decreasing process. As a result, the Cu-CCN samples exhibited enhanced photocatalytic CO2 reduction with nearly 100% selective photocatalytic CO2 to CO conversion. The mechanism of photocatalytic CO2 reduction over Cu-CCN samples was proposed based on in situ Fourier transform infrared spectra, X-ray absorption spectroscopy, and density functional theory calculation. This work provides an in-depth understanding of the design of photocatalysts for enhancing active sites of the reactants.